Oxybelondira penangi Ahmad and Jairajpuri, 1979

Ahmad, Wasim & Naz, Tabbasam, 2010, Two new and two known species of the family Belondiridae Thorne, 1939 (Nematoda: Dorylaimida) from Singapore, Journal of Natural History 44 (41 - 42), pp. 2465-2479 : 2477-2478

Oxybelondira penangi Ahmad and Jairajpuri, 1979

( Figures 5A–I, 6A–I; Table 2)

Description

Female. Body curved ventrad upon fixation, tapering towards both extremities. Cuticle with fine transverse striations, 2.0 µm thick at mid body and 3–4 µm on tail. Lateral chords with weakly developed glandular bodies, about one-third as wide as body width at mid body. Lateral, dorsal and ventral body pores indistinct. Lip region narrow, truncated, about twice as wide as high or about one-seventh to one-sixth as wide as body width at neck base; lips amalgamated and labial papillae not elevated. Cephalic framework strongly sclerotized. Amphids stirrup-shaped, their aperture about 0.7 times as wide as lip region width. Odontostyle thick-walled, about 1.3–1.5 times lip region width long, its aperture about one-third of its length. Guiding ring single, at 0.8 times lip region width from anterior end. Odontophore linear, 1.3 times the odontostyle length. Nerve ring at 30–35% of neck length from anterior end. Pharyngeal expansion gradual; expanded part occupying about 52–58% of total neck length and enclosed in a thick sheath of dextrally spiral muscles. Cardia rounded, about one-third to one-half of the corresponding body width long. Genital system monoopisthodelphic; anterior branch represented by a long uterine sac with rudimentary ovarial mass, measuring 50–100 µm or 2.5–3.5 times the corresponding body width long. Posterior branch well developed; ovary reflexed, reaching almost to oviduct– uterus junction, measuring 90–230 µm with oocytes arranged in a single row except near tip. Oviduct joining ovary subterminally, measuring 100–170 µm, consisting of a long slender part with prismatic cells and a slightly wider pars dilatata with wide lumen. Sphincter at oviduct–uterus junction weakly developed. Uterus simple undifferentiated tube, measuring 100–155 µm. Vulva transverse. Vagina extending inwards about one-third of corresponding body width; pars proximalis vaginae 3–5 µm long with almost straight walls; pars refringens vaginae absent; pars distalis vaginae 6–8 µm with curved walls. Pre-rectum 3.8–5.4 times anal body width long. Rectum about as long as anal body width. Tail first hemispherical then long filiform with acute terminus, arcuate dorsally, 8.4–9.6 times anal body width long. Caudal pores two on each side.

Male. Not found (spermatozoa not present in the female gonad).

Habitat and locality

Soil around the roots of forest trees from Kent Ridge Park, near National University of Singapore, Singapore.

Remarks

Ahmad and Jairajpuri (1979) described this species from Penang, Malaysia. The present specimens from Singapore conform well to the original description except for having a slightly longer expanded part of pharynx (52–58% vs 47–51%) and slightly shorter pre-rectum (3.8–5.4 vs 5.4–5.7 times anal body width long).